The point is if I upgrade my Debian 11 (with updated apache2
2.4.65-1~deb11u1, got trough usual official Debian repo) to 12, after
the upgrade apache2 from Debian 11 will be kept on a otherwise Debian
12, because it has a greater version number, and this may break the
system (FrankenDebian).
So, OK for the on-the-fly, less tested updates to bullseye, but it
should have had a version number lower than the one actually on Debian
12 (for example 2.4.62-1~deb11u1+2.4.65 ) to avoid the package to not
being upgraded to the proper Debian 12 version.
Or I am missing something?